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Isolation of Fidelity Variants of RNA Viruses and Characterization of Virus Mutation Frequency
Published on: June 16, 2011
Evolution of virulence in picornaviruses
S Tracy1, N M Chapman, K M Drescher
1Department of Pathology and Microbiology, University of Nebraska Medical Center, Omaha, NE 68198-6495, USA. stracy@unmc.edu
Current Topics in Microbiology and Immunology
|March 30, 2006
Summary
Picornaviruses cause diverse diseases, yet the genetic basis for their virulence is unclear. Virulence depends on viral genetics interacting with host factors, not specific virulence genes.
Area of Science:
- Virology
- Molecular Biology
- Pathogenesis
Background:
- Picornaviridae are positive-strand RNA viruses with similar genomes and capsids, causing varied diseases.
- Intra-serotype variations in picornavirus virulence indicate genetic determinants of pathogenesis.
- The genetic basis for picornavirus virulence is poorly understood.
Purpose of the Study:
- To explore the genetic factors influencing picornavirus virulence.
- To understand how viral genetics and host interactions determine disease severity.
Main Methods:
- Analysis of viral genome sequences, including capsid structure and non-translated regions.
- Investigation of viral interactions with host cell receptors.
- Examination of coding sequences and resulting protein variations.
Main Results:
- Picornavirus virulence is a complex phenotype influenced by multiple genetic elements.
- Capsid-receptor interactions, non-translated RNA sequences, and protein variations contribute to virulence.
- Virulence exists on a continuum, from asymptomatic infection to severe disease.
Conclusions:
- Picornavirus virulence is not determined by specific virulence genes but by a combination of genetic factors.
- Host-environment modulation of viral genetics is crucial for disease induction.
- Understanding these genetic elements is key to comprehending picornavirus pathogenesis.
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